ZyXEL Communications ACCESSING INTERNET & INTRANET omni series - Manual (Page 164)

152 Serial Port Interface
19
Serial Port Interface
EIA-232D 25 Pin Serial Port Interface
Pin
Number ITU-TSS
Signal
Name EIA
Signal
Name Signal/Pin
Description Signal
Direction
DTE -DCE
1 101 AA Protective Ground
(GND).
⇔
2 103 BA Transmitted
Data(TXD).
⇒
3 104 BB Received
Data(RXD).
⇐
4 105 CA Request To Send
(RTS).
⇒
5 106 CB Clear To Send
(CTS).
⇐
6 107 CC Data Set Ready
(DSR).
⇐
7 102 AB Signal Ground
(GND).
⇔
8 109 CF Data Carrier
Detected (DCD).
⇐
15 114 DB Transmit Clock
Signal (source:
DCE).
⇐
17 115 DD Synchronous Receive
Clock.
⇐
18 141 Local Analog
Loopback Test.
⇒
20 108/2
108/1 CD Data Terminal Ready
(DTR).
Connect DCE to line.
⇒
21 140 Remote Digital Loop
⇒